Your provided iframe code is from the last version of Fruitask, just clear your cache by hitting CTRL + F5, to solve your issue you just need to use forms add s from the from url. Let me fix it for you.
<iframe height="800" width="100%" style="border:none;" src="https://fruitask.com/forms/?p=YOUR_TOKEN" title="Fruitask"> </iframe>
Lemme know if it works.
